Providers Carlos O'Bryan-Becerra, M.D. to Amanda O'Connell, BCBA
300 individual NPIs in the federal registry, part 16,011 of 24,427 of the A to Z by surname. Each row is the registry's record: the name and credential, the NPI, the primary specialty, the practice city and the year the NPI was issued. 93 link to a page of their own with Medicare and CMS data the registry does not carry.
| Provider | NPI | Specialty | Practice city | NPI issued |
|---|---|---|---|---|
| Carlos O'Bryan-Becerra, M.D. | 1649422338 | Family Medicine Physician | Ventura, CA | 2008 |
| Alexander O'Bryan-Tear, PHD | 1952042608 | Professional Counselor | Portland, OR | 2022 |
| Aline O'Bryant | 1982397428 | Behavior Technician | Colorado Springs, CO | 2023 |
| Andrew O'Bryant, DO | 1790435931 | Physical Medicine & Rehabilitation Physician | Weatherford, TX | 2022 |
| Ashley O'Bryant, END OF LIFE DOULA | 1376431122 | Doula | Astoria, OR | 2025 |
| Bernard O'Bryant | 1972496545 | Case Manager/Care Coordinator | Columbus, OH | 2025 |
| Bridget O'Bryant | 1558604918 | Specialist | Keene, NH | 2013 |
| Brittany O'Bryant, M.S. | 1780256065 | Mental Health Counselor | Ball Ground, GA | 2021 |
| Calie O'Bryant | 1518526995 | Behavior Technician | Chesterfield, MI | 2019 |
| Callie O'Bryant, MD | 1912757063 | Emergency Medicine Physician | Birmingham, AL | 2024 |
| Carolyn O'Bryant, RN | 1437301462 | Registered Nurse | Pine Bluff, AR | 2008 |
| Catherine O'Bryant, CPM LDEM | 1245269414 | Midwife | Payson, UT | 2006 |
| Chris O'Bryant, DC | 1790844678 | Chiropractor | Salt Lake City, UT | 2006 |
| Cindy O'Bryant, PHARMD | 1871841486 | Oncology Pharmacist | Aurora, CO | 2012 |
| Curtis O'Bryant | 1033752605 | Behavior Technician | Charlotte, NC | 2019 |
| Daniel O'Bryant, ATC | 1114334281 | Athletic Trainer | Montgomery, AL | 2014 |
| Elliot O'Bryant | 1437662954 | Day Training/Habilitation Specialist | Ukiah, CA | 2017 |
| Emily O'Bryant, PTA | 1568047199 | Physical Therapy Assistant | Cleveland, GA | 2021 |
| Gregory O'Bryant, D.C. | 1174612378 | Chiropractor | Orem, UT | 2006 |
| Ivy O'Bryant | 1427847664 | Home Health Aide | Las Vegas, NV | 2025 |
| Jacob O'Bryant, PTA | 1215648985 | Physical Therapy Assistant | Memphis, TN | 2022 |
| Janae O'Bryant, DPT | 1043094618 | Physical Therapist | Middletown, RI | 2023 |
| Janice O'Bryant, M.S,. LPA, LPC | 1508985482 | Mental Health Counselor | Wilmington, NC | 2007 |
| Jerome O'Bryant | 1427329754 | Home Health Registered Nurse | Brooklyn, NY | 2012 |
| Johnny O'Bryant, CIT 3419 3/19/16 | 1417315946 | Addiction (Substance Use Disorder) Counselor | Baton Rouge, LA | 2016 |
| Kayla O'Bryant | 1164241543 | Behavior Technician | Tempe, AZ | 2024 |
| Kelly O'Bryant, LMSW | 1285097964 | Social Worker | La Fayette, GA | 2016 |
| Kelly O'Bryant, PMHNP-BC | 1871172213 | Psychiatric/Mental Health Nurse Practitioner | Gallipolis, OH | 2021 |
| Kili O'Bryant | 1881080018 | Emergency Medicine Physician | Palmer, AK | 2015 |
| Larry O'Bryant, MD | 1578614749 | Anatomic Pathology & Clinical Pathology Physician | Puyallup, WA | 2007 |
| Latorja O'Bryant, LCSW | 1326023409 | Clinical Social Worker | Augusta, GA | 2005 |
| Lindsey O'Bryant, AGNP-C | 1831591403 | Nurse Practitioner | Saint Louis, MO | 2014 |
| Madeline O'Bryant | 1679111645 | Behavior Technician | Lynn, MA | 2019 |
| Malika O'Bryant | 1932650777 | Mental Health Counselor | Westampton, NJ | 2016 |
| Mandy O'Bryant | 1740311901 | Case Manager/Care Coordinator | Prescott, AR | 2007 |
| Mariah O'Bryant, MSW | 1851757553 | Case Manager/Care Coordinator | Knoxville, TN | 2016 |
| Matthew O'Bryant | 1104952316 | Pharmacist | Saginaw, MI | 2007 |
| Melissa O'Bryant, RN | 1689371130 | Nurse Practitioner | Chapel Hill, NC | 2023 |
| Michael O'Bryant, LADC | 1588843296 | Addiction (Substance Use Disorder) Counselor | Manchester, NH | 2007 |
| Michael O'Bryant, DO | 1720548746 | Diagnostic Radiology Physician | Saint Louis, MO | 2019 |
| Michelle O'Bryant, LCSW | 1164708269 | Social Worker | Kingwood, TX | 2011 |
| Mindy O'Bryant, CRNP | 1346759438 | Family Nurse Practitioner | Southside, AL | 2017 |
| Molly O'Bryant, PHARM D | 1164900882 | Pharmacist | Pascagoula, MS | 2018 |
| Nicholas O'Bryant | 1740981232 | Case Manager/Care Coordinator | Delaware, OH | 2023 |
| Patricia O'Bryant, LPCC, LADC | 1205342383 | Mental Health Counselor | Minneapolis, MN | 2017 |
| Paula O'Bryant | 1144348525 | Physical Therapist | Fort Worth, TX | 2007 |
| Ramani O'Bryant | 1982558409 | Behavior Technician | Concord, CA | 2026 |
| Sharon O'Bryant, WHNP | 1659340487 | Women's Health Nurse Practitioner | Douglasville, GA | 2006 |
| Shelease O'Bryant, MD | 1164819975 | Pediatric Emergency Medicine (Pediatrics) Physician | Atlanta, GA | 2015 |
| Sidney O'Bryant, PHD | 1427084193 | Psychologist | Fort Worth, TX | 2006 |
| Slaine O'Bryant, MD | 1023868189 | Student in an Organized Health Care Education/Training Program | Birmingham, AL | 2024 |
| Stephan O'Bryant | 1609564962 | Case Manager/Care Coordinator | Quartz Hill, CA | 2023 |
| Stephanie O'Bryant, APRN | 1346433323 | Family Nurse Practitioner | Tampa, FL | 2007 |
| Steven O'Bryant, DPM | 1386050060 | Foot & Ankle Surgery Podiatrist | Chandler, AZ | 2014 |
| Stormy O'Bryant, PHARMD | 1992150049 | Pharmacotherapy Pharmacist | Alabaster, AL | 2016 |
| T'Challa O'Bryant, LPC | 1093402455 | Professional Counselor | Hinesville, GA | 2023 |
| Theresa O'Bryant, MSW, LCSWA | 1487508123 | Clinical Social Worker | Raleigh, NC | 2026 |
| Theresa O'Bryant, BCTMB, LMT | 1760953848 | Massage Therapist | Detroit, MI | 2018 |
| Tyra O'Bryant | 1568937977 | Occupational Therapy Assistant | Washington, DC | 2018 |
| William O'Bryant, M.D. | 1013041003 | Internal Medicine Physician | Cypress, CA | 2007 |
| Keara O'Bryen, LMSW | 1538918826 | Social Worker | Dix Hills, NY | 2024 |
| Bliss O'Bryhim, MD | 1427439298 | Retina Specialist (Ophthalmology) Physician | Saint Louis, MO | 2015 |
| James O'Bryon, O.D., M.D. | 1598742512 | Family Medicine Physician | Du Bois, PA | 2005 |
| Kelsey O'Bryon, PA-C | 1285149005 | Physician Assistant | Albany, NY | 2017 |
| Greta O'Buch, PA-C | 1689782989 | Physician Assistant | Asheboro, NC | 2006 |
| Matthew O'Bymachow | 1811713720 | Behavior Technician | Irvine, CA | 2024 |
| Brian O'Byrn, D.D.S. | 1104953710 | Orthodontics and Dentofacial Orthopedics Dentistry | Lake In The Hills, IL | 2007 |
| Allyn O'Byrne, RPH | 1992767685 | Pharmacist | Saint Louis, MO | 2006 |
| Amarina O'Byrne, FNP-C | 1477037323 | Family Nurse Practitioner | Mineola, TX | 2018 |
| Amy O'Byrne, P.A.-C | 1992084420 | Physician Assistant | Wichita, KS | 2011 |
| Brian O'Byrne | 1760923056 | Internal Medicine Physician | Elgin, IL | 2017 |
| Brian O'Byrne, MD | 1801896717 | Surgery Physician | Idaho Falls, ID | 2005 |
| Carole O'Byrne, CRNA | 1699874164 | Certified Registered Nurse Anesthetist | Minneapolis, MN | 2006 |
| Catherine O'Byrne | 1770335408 | Student in an Organized Health Care Education/Training Program | Orlando, FL | 2024 |
| Christina O'Byrne, MA, BCBA | 1467027706 | Behavior Analyst | Wilmington, NC | 2021 |
| Colleen O'Byrne, PSY.D. | 1194967935 | Clinical Psychologist | Washington, DC | 2009 |
| Dawn O'Byrne, PHD, RDN, LDN, RMHCI | 1730553140 | Registered Dietitian | Gainesville, FL | 2015 |
| Elizabeth O'Byrne | 1558295568 | Specialist | Seaford, NY | 2026 |
| Erin O'Byrne | 1841698198 | Speech-Language Pathologist | Bayside, NY | 2014 |
| Jaime O'Byrne, LCDC | 1578165106 | Addiction (Substance Use Disorder) Counselor | Sugar Land, TX | 2020 |
| Katie-Scarlett O'Byrne, PSY.D. | 1205202918 | Clinical Psychologist | Tacoma, WA | 2015 |
| Kyle O'Byrne | 1447187844 | Surgery Physician | Grand Blanc, MI | 2026 |
| Lora O'Byrne, O.T | 1891864534 | Hand Occupational Therapist | Overland Park, KS | 2006 |
| Margaret O'Byrne, M.D. | 1366543159 | Cardiovascular Disease Physician | San Diego, CA | 2006 |
| Marilu O'Byrne, M.D. | 1083772453 | Ophthalmology Physician | Mandeville, LA | 2006 |
| Mary O'Byrne | 1447513569 | Pharmacist | Spokane, WA | 2012 |
| Matthew O'Byrne, PH.D. | 1437425774 | Clinical Child & Adolescent Psychologist | San Rafael, CA | 2012 |
| Michael O'Byrne, M.D. | 1891992152 | Pediatric Cardiology Physician | Philadelphia, PA | 2007 |
| Nora O'Byrne, MD | 1073909826 | Endocrinology, Diabetes & Metabolism Physician | Merrionette Park, IL | 2015 |
| Rachel O'Byrne, MD | 1376503151 | Family Medicine Physician | Saint Clair Shores, MI | 2006 |
| Robert O'Byrne, APMH-NP/CNS | 1972774552 | Psychiatric/Mental Health Nurse Practitioner | Chesapeake, VA | 2008 |
| Robynne O'Byrne, PH.D. | 1508122128 | Clinical Psychologist | San Rafael, CA | 2012 |
| Stuart O'Byrne, MD | 1871608539 | Diagnostic Radiology Physician | Moses Lake, WA | 2006 |
| Tara O'Byrne, BCBA | 1619430006 | Behavior Analyst | Tampa, FL | 2019 |
| Taylor O'Byrne, PA-C | 1457158461 | Physician Assistant | Lakeland, FL | 2025 |
| Timothy O'Byrne, LBSW | 1407272404 | Social Worker | Wayne, MI | 2014 |
| Timothy O'Byrne, MD | 1538144514 | Cardiovascular Disease Physician | Staten Island, NY | 2005 |
| Armando O'Caa, LPC,M. ED. PH.D. | 1144203860 | Genetic Counselor (M.S.) | Mission, TX | 2005 |
| Anna O'Cain | 1164201901 | Mental Health Counselor | Brandon, MS | 2023 |
| Charles O'Cain, M.D. | 1568558088 | Pulmonary Disease Physician | Asheville, NC | 2006 |
| Debbie O'Cain, M.D. | 1689737272 | Family Medicine Physician | Memphis, TN | 2006 |
| Emma O'Cain | 1780431262 | Behavior Technician | Salt Lake City, UT | 2024 |
| Kristen O'Cain, LMFT | 1689064107 | Marriage & Family Therapist | Camarillo, CA | 2015 |
| Kristopher O'Cain | 1457161374 | Behavior Technician | Farmington Hills, MI | 2025 |
| Peggy O'Cain, MD | 1356392567 | Addiction Medicine (Preventive Medicine) Physician | Memphis, TN | 2006 |
| Peggy O'Cain, LPC | 1609294487 | Professional Counselor | Kingsland, GA | 2014 |
| Samuel O'Cain | 1275698664 | Contractor | Central, SC | 2006 |
| Sara O'Cain, PT | 1689411100 | Physical Therapist | Wakefield, RI | 2024 |
| Toni O'Cain, RN | 1831519297 | Registered Nurse | Orangeburg, SC | 2014 |
| Adrian O'Callaghan, MD | 1811339286 | Student in an Organized Health Care Education/Training Program | Cleveland, OH | 2013 |
| Alanna O'Callaghan | 1952131476 | Behavior Technician | San Francisco, CA | 2024 |
| Alexandra O'Callaghan | 1134018880 | Student in an Organized Health Care Education/Training Program | Pocatello, ID | 2025 |
| Amy O'Callaghan, DMD | 1811209604 | Pediatric Dentistry | Middletown, CT | 2010 |
| Barbara O'Callaghan, RN, NP | 1003041104 | Oncology Registered Nurse | Lawrenceville, GA | 2009 |
| Barry O'Callaghan, MB BCH BAO | 1700479565 | Student in an Organized Health Care Education/Training Program | Aurora, CO | 2021 |
| Brandon O'Callaghan, PHARMD | 1649437740 | Pharmacist | Elkins, WV | 2008 |
| Brenna O'Callaghan | 1588115570 | Social Worker | Red Bluff, CA | 2016 |
| Caitlin O'Callaghan, M.D. | 1760826945 | Emergency Medicine Physician | Lynchburg, VA | 2013 |
| Carolyn O'Callaghan, M.S.W. | 1528154945 | Social Worker | Hartford, CT | 2006 |
| Chris O'Callaghan | 1639448772 | Counselor | Kailua Kona, HI | 2011 |
| Christopher O'Callaghan, SLP MEDAID, CPR | 1306707658 | Adult Companion | Omaha, NE | 2025 |
| Claire O'Callaghan, MD | 1104760362 | Student in an Organized Health Care Education/Training Program | New York, NY | 2026 |
| Clare O'Callaghan, RN.C.S., ED.D | 1235280389 | Psychiatric/Mental Health Registered Nurse | Boston, MA | 2007 |
| Connor O'Callaghan, DPT | 1538029509 | Pediatric Physical Therapist | Shrewsbury, NJ | 2025 |
| Conor O'Callaghan, RBT | 1285597344 | Behavior Technician | Lexington, SC | 2025 |
| Conor O'Callaghan | 1619468576 | Clinical Social Worker | Willow Grove, PA | 2018 |
| Daniel O'Callaghan, DDS | 1467714956 | Pediatric Dentistry | Grand Rapids, MI | 2012 |
| Edileia O'Callaghan | 1205252715 | Social Worker | Fitchburg, MA | 2014 |
| Elizabeth O'Callaghan | 1558227629 | Specialist | Westbury, NY | 2026 |
| Ellen O'Callaghan | 1326984956 | Student in an Organized Health Care Education/Training Program | Philadelphia, PA | 2026 |
| Erin O'Callaghan, PH.D | 1932357621 | Clinical Child & Adolescent Psychologist | Los Angeles, CA | 2008 |
| Erin O'Callaghan, OTR/L | 1962156323 | Occupational Therapist | Naperville, IL | 2022 |
| Garrett O'Callaghan | 1164020632 | Behavior Technician | Riverside, CA | 2020 |
| Gina O'Callaghan, PA-C | 1003239500 | Physician Assistant | Portage, MI | 2014 |
| Gina O'Callaghan, LMSW | 1730540337 | Social Worker | Perry Point, MD | 2016 |
| Grace O'Callaghan, OT | 1316804842 | Occupational Therapist | Dedham, MA | 2026 |
| Ian O'Callaghan | 1356572242 | Counselor | Lummi Island, WA | 2009 |
| James O'Callaghan, MD, FAAP SFHM | 1053406397 | Pediatrics Physician | Seattle, WA | 2006 |
| James O'Callaghan, PA-C | 1548408347 | Medical Physician Assistant | Fleming Island, FL | 2009 |
| James O'Callaghan, PH.D. | 1689796690 | Marriage & Family Therapist | New Milford, CT | 2007 |
| Jamie O'Callaghan, PCLC | 1538090899 | Mental Health Counselor | Bozeman, MT | 2026 |
| Jennifer O'Callaghan | 1891268975 | Community Health Worker | Worland, WY | 2019 |
| Joe O'Callaghan, LCSW | 1013431444 | Clinical Social Worker | Norwalk, CT | 2017 |
| Judith O'Callaghan, LMFT, LADC | 1508988510 | Marriage & Family Therapist | New Milford, CT | 2007 |
| Justine O'Callaghan | 1922554310 | Speech-Language Pathologist | Apex, NC | 2016 |
| Kaleen O'Callaghan | 1518313816 | Mental Health Counselor | San Luis Obispo, CA | 2016 |
| Katherine O'Callaghan, LMHC | 1871714618 | Mental Health Counselor | Beverly, MA | 2007 |
| Keri O'Callaghan | 1568900702 | Behavior Analyst | Fresno, CA | 2017 |
| Kevin O'Callaghan, M.D. | 1063642627 | Pediatric Infectious Diseases Physician | Philadelphia, PA | 2009 |
| Leah O'Callaghan, C-AA | 1184115453 | Anesthesiologist Assistant | Atlanta, GA | 2018 |
| Madeleine O'Callaghan, PT, DPT | 1881209732 | Physical Therapist | Cadillac, MI | 2020 |
| Maeve O'Callaghan | 1285276287 | Massage Therapist | Portland, OR | 2019 |
| Margaret O'Callaghan, NURSE PRACTITIONER | 1184507014 | Family Nurse Practitioner | Chicago, IL | 2025 |
| Margaret O'Callaghan, ANP-BC, WHNP-BC | 1881818110 | Nurse Practitioner | Middleton, MA | 2007 |
| Marissa O'Callaghan, MB BCH BAO | 1043743875 | Internal Medicine Physician | Scottsdale, AZ | 2017 |
| Mark O'Callaghan, M.D. | 1023180890 | Neuroradiology Physician | Tacoma, WA | 2006 |
| Mary O'Callaghan, PT | 1265740922 | Physical Therapist | Blauvelt, NY | 2010 |
| Mary O'Callaghan | 1467165753 | Occupational Therapist | Slidell, LA | 2023 |
| Mary O'Callaghan, M.D. | 1932489408 | Family Medicine Physician | El Segundo, CA | 2011 |
| Maureen O'Callaghan | 1902754690 | Occupational Therapist | Seaford, NY | 2026 |
| Maureen O'Callaghan, M.A | 1962820985 | Speech-Language Pathologist | Anchorage, AK | 2014 |
| Michael O'Callaghan, MD | 1033256318 | Anesthesiology Physician | Denver, CO | 2007 |
| Michael O'Callaghan, DDS | 1386622017 | Dentist | Allegan, MI | 2006 |
| Michael O'Callaghan, PHD | 1609951292 | Clinical Psychologist | San Diego, CA | 2006 |
| Naomi O'Callaghan, CPM | 1952636805 | Midwife | North Las Vegas, NV | 2009 |
| Neal O'Callaghan, PA-C | 1497762454 | Family Medicine Physician | Albuquerque, NM | 2006 |
| Patrick O'Callaghan, PH.D. | 1386908754 | Clinical Psychologist | Metairie, LA | 2012 |
| Patrick O'Callaghan, M.D. | 1750792446 | Orthopaedic Surgery Physician | Charleston, SC | 2014 |
| Pgayle O'Callaghan, PSY.D. | 1154864437 | Clinical Psychologist | Severna Park, MD | 2016 |
| Priya O'Callaghan, D.D.S. | 1912030420 | Endodontics | Oakland, CA | 2007 |
| Rebecca O'Callaghan, M.S., OTR/L, SWC | 1720392434 | Pediatric Occupational Therapist | Sacramento, CA | 2010 |
| Robert O'Callaghan, PA | 1518906254 | Medical Physician Assistant | Vandalia, OH | 2006 |
| Rory O'Callaghan, PHARM.D. | 1801100722 | Pharmacist Clinician (PhC)/ Clinical Pharmacy Specialist | Los Angeles, CA | 2010 |
| Ryan O'Callaghan, MBA | 1588295042 | Case Manager/Care Coordinator | Concord, NH | 2020 |
| Sally O'Callaghan, FNP | 1912997214 | Family Nurse Practitioner | New Hartford, NY | 2005 |
| Sarah O'Callaghan, RD | 1710861216 | Registered Dietitian | Springfield, MO | 2025 |
| Shea O'Callaghan, LMFT | 1174107783 | Marriage & Family Therapist | Waltham, MA | 2021 |
| Sheila May O'Callaghan, NP | 1821492893 | Gerontology Nurse Practitioner | Fayetteville, NC | 2014 |
| Sherrie O'Callaghan | 1043865587 | Family Nurse Practitioner | North Port, FL | 2019 |
| Sianna O'Callaghan | 1992375455 | Behavior Technician | Farmington Hills, MI | 2021 |
| Sondra O'Callaghan, PA | 1477702538 | Medical Physician Assistant | Orlando, FL | 2008 |
| Stasha O'Callaghan, MD | 1154812998 | Student in an Organized Health Care Education/Training Program | New York, NY | 2018 |
| Stephanie O'Callaghan, PH.D. | 1467685164 | Clinical Psychologist | White Plains, NY | 2009 |
| Tammy O'Callaghan | 1225422595 | Hearing Instrument Specialist | Zachary, LA | 2015 |
| Tanya O'Callaghan, OT | 1720277833 | Pediatric Occupational Therapist | Puyallup, WA | 2007 |
| Terr2 O'Callaghan, RPH | 1700857737 | Pharmacist | Bend, OR | 2006 |
| Thomas O'Callaghan, MD | 1265926331 | Internal Medicine Physician | Ann Arbor, MI | 2018 |
| Thomas O'Callaghan, MD | 1699751321 | Surgery Physician | Loma Linda, CA | 2005 |
| Vanessa O'Callaghan, M.A., CCC-SLP | 1013559111 | Speech-Language Pathologist | Rye Brook, NY | 2019 |
| W O'Callaghan | 1932294816 | Internal Medicine Physician | Santa Barbara, CA | 2006 |
| William O'Callaghan, M.D. | 1457390619 | Cardiovascular Disease Physician | Scottsdale, AZ | 2006 |
| Katherine O'Callaghan Estes | 1659666949 | Mental Health Counselor | Portland, OR | 2011 |
| Colleen O'Callaghan-Miele | 1376084400 | Specialist | Las Vegas, NV | 2017 |
| Arlene O'Callahan, LPN | 1215367040 | Licensed Practical Nurse | New Haven, CT | 2013 |
| Clare O'Callahan, LMHC | 1851632053 | Mental Health Counselor | Astoria, NY | 2013 |
| Cliff O'Callahan, M.D., PH.D. | 1811977663 | Pediatrics Physician | Middletown, CT | 2006 |
| Elena O'Callahan, RD | 1134687593 | Registered Dietitian | Everett, WA | 2019 |
| Elizabeth O'Callahan, MD | 1346773074 | Family Medicine Physician | Brooklyn, NY | 2017 |
| Elizabeth O'Callahan, LMHC, BCBA, LABA | 1548531916 | Mental Health Counselor | Worcester, MA | 2012 |
| Joley O'Callahan, MD | 1588160394 | Vascular & Interventional Radiology Physician | North Kansas City, MO | 2018 |
| Julianne O'Callahan, MD | 1932158805 | Obstetrics & Gynecology Physician | Redwood City, CA | 2006 |
| Kristi O'Callahan, MSED. | 1538408687 | Specialist | Washingtonville, NY | 2013 |
| Ornela O'Callahan, RN | 1336090273 | Registered Nurse | Lakewood, NJ | 2026 |
| Patrick O'Callahan, M.D. | 1386733988 | Preventive Medicine/Occupational Environmental Medicine Physician | Stonington, CT | 2006 |
| William O'Callahan, MD | 1114964186 | Emergency Medicine Physician | Holden, MA | 2006 |
| Chelsea O'Camb | 1831940436 | Student in an Organized Health Care Education/Training Program | Los Angeles, CA | 2024 |
| Sean O'Came, PA-C | 1376817544 | Surgical Physician Assistant | East Setauket, NY | 2012 |
| Aida O'Campo | 1265992952 | Behavior Technician | Anaheim, CA | 2019 |
| Griselda O'Campo | 1497027551 | Mental Health Counselor | Ontario, CA | 2012 |
| Joanna O'Campo, PA-C | 1750655288 | Physician Assistant | Yuma, AZ | 2012 |
| Kelly O'Campo | 1790559284 | Behavior Technician | Ontario, CA | 2023 |
| Manuela O'Campo, MD | 1336130723 | Obstetrics & Gynecology Physician | St Clair Shores, MI | 2005 |
| Nholbie O'Campo | 1770242687 | Home Health Aide | Sparks, NV | 2021 |
| Denise O'Cana | 1417343013 | Specialist | Pueblo, CO | 2015 |
| Rhonda O'Cana, L.P.C. | 1144437229 | Mental Health Counselor | San Antonio, TX | 2007 |
| Tony O'Cana, B.A. SOCIOLOGY | 1033343686 | Community Health Worker | Pueblo, CO | 2009 |
| Francisca O'Canas, LPC | 1356382741 | Professional Counselor | San Antonio, TX | 2006 |
| Allen O'Carey, MSW, LSW | 1144829961 | Counselor | South Bend, IN | 2020 |
| Brian O'Carroll, DPM | 1336133768 | Foot & Ankle Surgery Podiatrist | Pismo Beach, CA | 2005 |
| Canna O'Carroll, LPC | 1770101297 | Mental Health Counselor | Elizabeth, CO | 2020 |
| Cathy O'Carroll | 1366330599 | Dental Hygienist | Princeton, NJ | 2025 |
| Christopher O'Carroll, M.D. | 1720187487 | Neurology Physician | Newport Beach, CA | 2006 |
| Colleen O'Carroll | 1861897852 | Occupational Therapy Assistant | Middletown, NY | 2014 |
| Cumara O'Carroll, M.D. | 1215161898 | Neurology Physician | Scottsdale, AZ | 2009 |
| Darragh O'Carroll, M.D. | 1538421565 | Emergency Medicine Physician | Los Angeles, CA | 2012 |
| Donal O'Carroll, LCAS-A, LCMHC-A | 1144901778 | Addiction (Substance Use Disorder) Counselor | Hickory, NC | 2023 |
| Emily O'Carroll, PA-C | 1205321288 | Physician Assistant | Lake Katrine, NY | 2018 |
| Ishara O'Carroll | 1437632213 | Clinical Social Worker | Stamford, CT | 2018 |
| James O'Carroll | 1275109704 | Anesthesiology Physician | Palo Alto, CA | 2021 |
| James O'Carroll, DDS | 1376816496 | General Practice Dentistry | Des Plaines, IL | 2012 |
| Jessica O'Carroll | 1811381627 | Physician Assistant | Ocala, FL | 2015 |
| Karen O'Carroll | 1780701607 | Speech-Language Pathologist | Diamond Point, NY | 2007 |
| Kathleen O'Carroll, BS | 1669862538 | Counselor | Gloucester, MA | 2015 |
| Kelly O'Carroll, MD | 1669677159 | Internal Medicine Physician | Granbury, TX | 2007 |
| Patrick O'Carroll, MD, MPH | 1578253662 | Family Medicine Physician | Decatur, GA | 2023 |
| Peter O'Carroll, M.D. | 1811190812 | Neurology Physician | Granbury, TX | 2007 |
| Richard O'Carroll, MHC | 1578224523 | Mental Health Counselor | Tulsa, OK | 2022 |
| Sean O'Carroll | 1366735268 | Rehabilitation Practitioner | Yerington, NV | 2011 |
| Shannon O'Carroll, APC | 1992535066 | Professional Counselor | Gainesville, GA | 2024 |
| Siobhan O'Carroll, OD | 1558353383 | Optometrist | Eau Claire, WI | 2005 |
| Susan O'Carroll, PT | 1174572812 | Physical Therapist | Wilmington, NC | 2006 |
| Eileen O'Casey, MS OTR/L | 1740798321 | Occupational Therapist | Arlington, VA | 2018 |
| Tamara O'Casey, OT | 1790195626 | Pediatric Occupational Therapist | Albuquerque, NM | 2014 |
| Roisin O'Cearbhaill, MB BCH | 1821241043 | Medical Oncology Physician | New York, NY | 2008 |
| Emily O'Chiu, RD | 1902171051 | Registered Dietitian | Saint Louis, MO | 2012 |
| Dallas O'Clair, BCBA | 1063159747 | Behavior Analyst | New Port Richey, FL | 2022 |
| Desiree O'Clair, CD(DONA) | 1730418294 | Doula | West Hurley, NY | 2009 |
| Karin O'Clair, D.O. | 1598726051 | Family Medicine Physician | Phoenix, AZ | 2006 |
| Morgan O'Clair | 1215399191 | Physical Therapist | Catonsville, MD | 2016 |
| Olivia O'Clair | 1841152972 | Mental Health Counselor | Winston Salem, NC | 2025 |
| Ryan O'Clair, AUD | 1386011401 | Audiologist | Bend, OR | 2015 |
| Aimee O'Claire O'Claire | 1497155014 | Massage Therapist | Roselle, IL | 2014 |
| Kathleen O'Claire | 1790495828 | Behavior Technician | Concord, CA | 2022 |
| Tonya O'Claire, RN | 1649508862 | Gerontology Registered Nurse | Guerneville, CA | 2009 |
| Marc O'Cleireachain, MD | 1235306549 | Surgery Physician | Tucson, AZ | 2008 |
| Michelle O'Cleireachain, PSYD | 1063035541 | Clinical Psychologist | Tucson, AZ | 2020 |
| Conall O'Cleirigh, PHD | 1417159245 | Clinical Psychologist | Boston, MA | 2007 |
| Deaglan O'Cochlain, M.D. | 1982677274 | Cardiovascular Disease Physician | Eau Claire, WI | 2006 |
| Selina O'Coffey, LMFT | 1558791913 | Marriage & Family Therapist | La Grange, KY | 2013 |
| Rachel O'Coin, LCSW | 1477988301 | Clinical Social Worker | Manchester, CT | 2013 |
| Taylin O'Coin, MA | 1073033932 | Counselor | Worcester, MA | 2017 |
| Terrence O'Collins, D.C. | 1609093350 | Chiropractor | Clovis, CA | 2007 |
| Hailey O'Como, CCC-SLP | 1801529607 | Speech-Language Pathologist | Anoka, MN | 2022 |
| Charles O'Con, CRNA | 1649382201 | Certified Registered Nurse Anesthetist | Shreveport, LA | 2006 |
| Dayna O'Con | 1669845061 | Behavior Analyst | Robeline, LA | 2015 |
| Katrina O'Con, CRNA | 1124019476 | Certified Registered Nurse Anesthetist | Shreveport, LA | 2005 |
| Marcela O'Con | 1366764300 | Certified Registered Nurse Anesthetist | Yorba Linda, CA | 2010 |
| Miriam O'Con | 1174491625 | Case Manager/Care Coordinator | Fairfield, CA | 2025 |
| Trini O'Con, HS | 1649355405 | Other Specialist/Technologist | Key West, FL | 2006 |
| Danielle O'Conke, DO | 1881498954 | Student in an Organized Health Care Education/Training Program | Cleveland, OH | 2025 |
| Vanessa O'Conneli | 1952874745 | Behavior Technician | Sacramento, CA | 2019 |
| Aaron O'Connell | 1073074712 | Behavior Technician | Miramar, FL | 2019 |
| Aaron O'Connell, CRNA | 1467304584 | Certified Registered Nurse Anesthetist | Duluth, MN | 2026 |
| Abigail O'Connell | 1346877198 | Nurse Practitioner | Philadelphia, PA | 2020 |
| Abigail O'Connell, MS, APRN, FNP-C | 1639543689 | Family Nurse Practitioner | Charleston, SC | 2015 |
| Abigail O'Connell, PA | 1942199617 | Physician Assistant | Milford, MA | 2025 |
| Addie O'Connell | 1649696865 | Mental Health Counselor | Ottawa, KS | 2014 |
| Adrienne O'Connell, CNM | 1285936286 | Advanced Practice Midwife | Arlington, MA | 2010 |
| Agatha O'Connell | 1588101737 | Certified Registered Nurse Anesthetist | Jacksonville, FL | 2017 |
| Aileen O'Connell | 1093452310 | Speech-Language Pathologist | Westbury, NY | 2022 |
| Aimee O'Connell, PHARMD | 1124744214 | Pharmacist | Lawrence, MA | 2022 |
| Aimee O'Connell | 1356823124 | Social Worker | Port Jefferson, NY | 2018 |
| Alanna O'Connell, D.O. | 1396134821 | Emergency Medicine Physician | Philadelphia, PA | 2015 |
| Albert O'Connell, LCSW | 1922250380 | Clinical Social Worker | Westhampton Beach, NY | 2008 |
| Alec O'Connell, PT | 1720755754 | Physical Therapist | Honolulu, HI | 2021 |
| Alex O'Connell, CRNA | 1598153462 | Certified Registered Nurse Anesthetist | Rhinebeck, NY | 2014 |
| Alexander O'Connell, MD | 1699206722 | Internal Medicine Physician | Greenlawn, NY | 2017 |
| Alexandra O'Connell, DNP, APN, AGPCNP-C | 1992569313 | Nurse Practitioner | Egg Harbor Township, NJ | 2024 |
| Alison O'Connell, LICSW | 1952560393 | Clinical Social Worker | Burlington, MA | 2008 |
| Alissa O'Connell, PHARM. D. | 1821215401 | Pharmacist | Snohomish, WA | 2007 |
| Allison O'Connell | 1376147736 | Professional Counselor | Chicago, IL | 2020 |
| Allison O'Connell, MA | 1821159237 | Mental Health Counselor | Brockton, MA | 2006 |
| Allison O'Connell | 1821681230 | Behavior Technician | Fort Collins, CO | 2021 |
| Allyson O'Connell, CRNP | 1730995705 | Family Nurse Practitioner | Washington, PA | 2024 |
| Allysyn O'Connell, PHYSICAL THERAPIST | 1003128562 | Physical Therapist | Victor, NY | 2010 |
| Alycia O'Connell, LCSW, CADC III, CSSW | 1417144262 | Clinical Social Worker | Troutdale, OR | 2007 |
| Alyson O'Connell | 1215583752 | Physical Therapist | Houston, TX | 2019 |
| Alyssa O'Connell, LMSW | 1487446951 | Clinical Social Worker | Brooklyn, NY | 2025 |
| Alyssandra O'Connell, MS | 1003685306 | Speech-Language Pathologist | Lake Ronkonkoma, NY | 2023 |
| Amanda O'Connell, BCBA | 1306357751 | Behavior Analyst | Fenton, MI | 2017 |
Source: CMS National Plan and Provider Enumeration System (NPPES) (download.cms.gov). A listing is not a recommendation: check a license with the state board (license lookups).